Soundtrack albums

Factual Questions
1

So…why do the songs on soundtrack albums sound different from how they appeared in movies? I’m not talking of songs being of different lengths (editing, that is), nor do I mean the differences between, say, the stage shows (in some cases) and movies…I mean a movie comes out with some musical numbers, and the musical numbers are different on the soundtrack album. I can think of a few examples off the top of my head…

Grease – “Greased Lightning” has a few different lyrics.

Hair – Dorsey Wright solos on the bridge of the title song, but on the soundtrack album Treat Williams takes it, possibly doubling with Don Dacus. In the movie, there’s a brief muted trumpet solo before Treat Williams sings the “Manchester” reprise in “The Flesh Failures,” but on the soundtrack album the trumpet solo is spliced in so that it’s in the background of the Treat Williams vocal.

Blues Brothers – “Everybody Needs Somebody To Love” has female backup vocalists on the soundtrack recording, but there aren’t any such vocalists in the movie. “Gimme Some Lovin’” is a completely different recording (although you could argue that it’s on the album as a bonus). “Think” is an almost completely different arrangement in the movie from how it appears on the album – including an instrumental intro on the album not present in the movie.

Yellow Submarine – “It’s All Too Much” has a verse in the movie version that to this day has yet to see any kind of non-bootlegged audio release.

So…why do they do these things??? Why not just put the movie versions on the soundtrack albums???

2

Various reasons, including the fact that the records are being made independently of the films.

Thus if a verse is cut out in editing the film, the word to cut it doesn’t necessarily get to the soundtrack company. Or if the record producer thinks the song will sound better rearranged, then he does it that way. Or perhaps the recording producer prefers take 2 of the song while the director prefers take 6.